Early detection of the presence of microbes, toxins or other components in food and/or water or the early detection of infection is a long desired goal in preventing human diseases. For example, cholera continues to be a major public health concern in developing countries. The disease is a toxin-mediated bacterial infection, caused by certain serogroups of Vibrio cholerae, that has the ability to cause outbreaks of epidemic proportions. In the last 200 years there have been at least 7 cholera pandemics, of which the latest still continues.
The current pandemic, which began in 1961 in Indonesia, has now circled the globe, affecting countries in Asia, Africa, Europe and South America. In 2003 outbreaks were reported in many countries, including South Africa, Mozambique, the Democratic Republic of the Congo, Liberia and Iraq.
Similarly, malaria is another major health issue in developing countries especially in tropical Africa and Asia. While malaria is curable, efficacious treatment requires early diagnosis and prompt treatment. Conventionally, the presence of malaria in a patient correlates to the presence of the malarial enzyme pGluDH (Glutamate dehydrogenase) or lactate dehydrogenase which is not present in human blood cells.
Current diagnostic tests for such diseases can be relatively expensive and may require the aid of a skilled technician to interpret such tests. These limitations pose challenges to using these tests in developing countries where they are needed the most.
As outbreaks of these and other diseases due to microbial toxins or the microbes themselves occur in developing or third-world countries. There the accurate diagnosis of such diseases remains a challenge due to lack of resources such as the availability of equipment typically used for detection in routine assays. In addition to such cost concerns, challenges in the detection of disease faced by individuals in these regions of the world also include the lack of trained individuals to properly use and evaluate the results provided by the detection instrumentation.
Thus, there is a need in the art for diagnostic assays that allow for rapid and accurate detection of microbial mediated diseases. Furthermore, there is also a need for assays that, in general, are easy to use and easy to interpret regardless of the technical skill of the individual performing the assay.